Descartes Quote by John Stuart Mill
““Logic, according to the conception here formed of it, has no concern with the nature of the act of judging or believing; the consideration of that act, as a phenomenon of the mind, belongs to another science. Philosophers, however, from Descartes downward, and especially from the era of Leibnitz and Locke, have by no means observed this distinction; and would have treated with great disrespect any attempt to analyze the import of Propositions, unless founded on an analysis of the act of Judgment.””
About This Quote
Source Book: System of Logic, John Stuart Mill, 1843
Mill argues that logic studies the form of propositions, not the mental act of judgment, which belongs to psychology.
In simple terms: Logic deals with propositions, not how we think.
Key Takeaway
Separate logical analysis from psychological study.
Themes
logic
philosophy
epistemology
Mood
analytical
critical
Type
philosophical
academic
When to use this quote
- academic research
- teaching logic
- philosophical debate
- psychology of reasoning
Key Concepts
proposition analysis
mental act
philosophical methodology
Questions to Reflect On
- How does separating logic from psychology affect our understanding of reasoning?
- Can logical forms be fully grasped without considering mental processes?
A Different Perspective
Neglecting the mental act can oversimplify reasoning processes.
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